A team of about a dozen National Transportation Safety Board investigators arrived in Alabama Wednesday to begin their probe into a deadly charter bus crash on Interstate 10 in Baldwin County.

They are the first of several groups who will most likely be here for more than week, gathering evidence and piecing together what went wrong Tuesday morning. But the cause of the crash won't be known for a while, we're told.

About a dozen federal investigators met with local officials at 10 a.m. at the Baldwin County Emergency Management Agency facility in Robertsdale. Afterward, they divided into three teams that will look into the crash, in which a bus operated by First Class Tours carrying band members from Channelview High School of Texas plunged into a 50-foot ravine when it left a westbound I-10 travel lane near mile marker 57, east of the Florida state line.

Local authorities say the bus veered off I-10 west, went into the eastbound lanes of I-10 and bounced off a guard rail, before plunging down a steep ravine.

About 45 people were on board the bus, authorities have said.

The bus driver, Harry Caligone, died in the 5:30 a.m. Tuesday crash that shut down I-10 for hours. More than two dozen others were hurt, with bus passengers transported to hospitals in Pensacola, Fla., as well as in Mobile and Baldwin County in Alabama.

The three NTSB teams are examining:

The bus, which was removed from the crash scene at midday Tuesday and taken to Fairhope.

The scene (environment), including examining the highway conditions and path taken by the bus.

The driver, including talking to witnesses and passengers.

NTSB officials started the long investigation Wednesday morning, looking at the crash site, and the crushed bus, which could be equipped with technology helpful to the investigation. Certain devices on the bus could be key to figuring out what went wrong. NTSB held a news conference Wednesday afternoon, to explain their strategy, while crews continued to investigate.

"Motor coaches, as most cars are, are not equipped with a black box that tells you everything that happened at every moment…we are uncertain at this stage in the game what devices are on this bus, we're taking hard look at that," said senior highway safety investigator Pete Kotowski.

Officials tell FOX10 News the bus was new, only on its second trip. It was scheduled to leave Orlando at 10:00 Monday night. The driver was near the end of his shift and was supposed to meet a relief driver in Mobile. We're told bus drivers are legally allowed to drive for ten hours before getting a break. Investigators say, the bus that crashed was in front of a second bus with the other half of the band, when it lost control.

NTSB says the bus did have seat belts. We're told some of the passengers were wearing them at the time of the crash. Investigators will look into the structure of the bus, and how it withstood the impact. Kotowski says some safety features on the bus could have been instrumental in saving lives.

"It isn't just one single event or one single circumstance, often times it's a number of events or circumstances that all collectively come together, and the result is a crash," said Kotowski.

To look at all of those circumstances, we're told NTSB crews will be going back and forth between the scene and where the wrecked bus is in Fairhope. Investigators are also still interviewing passengers, but have talked to most of them. The whole investigation could take up to a year.

One parent who had a son on the bus says she wants answers as to what happened.

"To know that my son is OK, puts me at ease," said Frances Dodson, mother of a bus passenger. "But to know that something like this happened, I mean you have questions. I mean, what caused the accident?"

On Wednesday, Sacred Heart Hospital in Pensacola reports three patients in serious condition and two in good condition. Thomas Hospital in Baldwin County lists three patients in stable condition. In Mobile, crash survivors in hospitals included one in stable condition at Mobile Infirmary and two in fair condition at USA Medical Center.

“I felt hopeless and like I couldn’t do anything,” said Josh Torres, the brother of one of the victims. “It was scary. I legitimately thought my sister was dead and then I wouldn’t be able to see her again.”

Thankfully, Josh said, his 17-year-old sister, Bianca Torres, is OK. She is bruised but has no serious injuries.

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17-year-old Bianca Torres plays percussion for the Channelview High School Band. She survived the deadly charter bus crash without serious injury, according to her brother. (Courtesy: Josh Torres)

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“I felt hopeless and like I couldn’t do anything,” said Josh Torres, the brother of one of the victims. “It was scary. I legitimately thought my sister was dead and then I wouldn’t be able to see her again.”

“I felt hopeless and like I couldn’t do anything,” said Josh Torres, the brother of one of the victims. “It was scary. I legitimately thought my sister was dead and then I wouldn’t be able to see her again.”